2026/2027) Human Anatomy & Physiology I with Lab |
Questions & Answers | Grade A 100% Correct -
Portage Learning
Bone Tissue & Skeletal System Foundations
Q1: While reviewing the histology of bone tissue in the lab, you observe a central canal
with concentric rings of matrix surrounding it. This structural unit is best known as a(n):
A. Canaliculus
B. Trabecula
C. Osteon [CORRECT]
D. Lamella
Correct Answer: C
Rationale: The osteon, or Haversian system, is the functional unit of compact bone,
consisting of a central canal surrounded by concentric lamellae.
Q2: Which of the following cell types is primarily responsible for breaking down bone
matrix to release minerals into the bloodstream?
A. Osteoblast
B. Osteocyte
C. Osteoclast [CORRECT]
D. Chondrocyte
Correct Answer: C
Rationale: Osteoclasts are the bone-resorbing cells that secrete acids and enzymes to
dissolve the bone matrix during remodeling or calcium release.
Q3: A student asks why organic components are necessary in the bone matrix. You
explain that the organic component, primarily collagen, provides:
A. Hardness and rigidity
B. Tensile strength and flexibility [CORRECT]
C. The main source of calcium storage
D. Weight-bearing stability
Correct Answer: B
Rationale: While minerals like calcium phosphate provide hardness and rigidity, the
collagen fibers give bone its tensile strength and flexibility, preventing it from being
brittle.
,Q4: During intramembranous ossification, mesenchymal cells differentiate directly into
osteoblasts without a cartilage model. Which of the following bones is formed primarily
through this process?
A. Femur
B. Humerus
C. Frontal bone [CORRECT]
D. Vertebral body
Correct Answer: C
Rationale: Intramembranous ossification forms flat bones of the skull, like the frontal
bone, as well as the mandible and clavicles.
Q5: In the process of endochondral ossification, what structure replaces the cartilage
model to form the primary ossification center?
A. Spongy bone [CORRECT]
B. Compact bone only
C. Marrow cavity
D. Articular cartilage
Correct Answer: A
Rationale: The primary ossification center is where the cartilage model is calcified and
broken down, replaced by spongy (trabecular) bone, which is later remodeled.
Q6: You are examining a slide of hyaline cartilage that is transitioning into bone. You
identify a band of ossification that runs lengthwise across the bone, indicating the site of
growth in length. This structure is the:
A. Epiphyseal line
B. Epiphyseal plate [CORRECT]
C. Perichondrium
D. Periosteum
Correct Answer: B
Rationale: The epiphyseal plate is the growth plate made of hyaline cartilage; it allows
for longitudinal growth of long bones during childhood and adolescence.
Q7: Which of the following hormones would be most active in lowering blood calcium
levels by stimulating bone deposition?
A. Parathyroid Hormone (PTH)
B. Calcitonin [CORRECT]
C. Growth Hormone
D. Thyroxine
Correct Answer: B
Rationale: Calcitonin functions to lower blood calcium levels by inhibiting osteoclasts
and stimulating osteoblasts to deposit calcium into the bone matrix.
, Q8: When a bone fracture occurs, a hematoma forms first. Which of the following
events immediately follows the formation of the hematoma during the repair process?
A. Formation of a fibrocartilaginous callus [CORRECT]
B. Remodeling of compact bone
C. Formation of a bony callus
D. Osteoclast activity removes the dead bone
Correct Answer: A
Rationale: After the hematoma, capillaries grow into the area and fibroblasts and
chondroblasts produce a fibrocartilaginous callus to bridge the gap.
Q9: A patient presents with a fracture in the diaphysis of a long bone. To help stabilize
the bone, the surgeon creates a hole to insert a pin. Which layer of the bone tissue must
the drill penetrate immediately after passing through the periosteum?
A. Medullary cavity
B. Endosteum
C. Compact bone [CORRECT]
D. Spongy bone
Correct Answer: C
Rationale: Deep to the periosteum is the dense compact bone that forms the hard outer
shaft (diaphysis) of long bones.
Q10: Small channels that radiate from the central canal, allowing osteocytes to
communicate with each other and exchange nutrients via gap junctions, are called:
A. Canaliculi [CORRECT]
B. Volkmann's canals
C. Perforating canals
D. Lacunae
Correct Answer: A
Rationale: Canaliculi are tiny canals that connect lacunae (which house osteocytes) to
the central canal, facilitating nutrient and waste transport.
Q11: Which of the following best describes the function of the red marrow found in the
spongy bone of the epiphyses?
A. Fat storage
B. Hematopoiesis [CORRECT]
C. Bone mineral storage
D. Secretion of synovial fluid
Correct Answer: B
Rationale: Red marrow is responsible for hematopoiesis, the production of red blood
cells, white blood cells, and platelets.